This invention relates to low voltage detecting devices and particularly to a low voltage warning apparatus for providing an indicating signal when a voltage below an acceptable level is sensed. The invention also encompasses a method of providing a low voltage warning signal.
Local electrical power distribution systems occasionally provide AC power at voltage levels below the standard level of approximately 110 volts, particularly in times of high electrical power demand. Although no electrical distribution system is completely immune to the problem of providing a low voltage signal, small distribution systems are most likely to occasionally provide AC signals below the standard 110 volt level. For example, low voltage conditions commonly occur in recreational vehicle or RV parks as such parks fill up at night and electrical consumption increases. Also, small portable AC generators such as those commonly carried by RVs may provide AC power below the standard voltage level when overloaded.
Although low AC voltage may be supplied by an electrical power distribution system under a number of different circumstances, many electrically powered devices are specifically adapted to operate on alternating current at the standard 110 volt level and may be damaged if operated on alternating current at voltage levels below the standard level. AC electric motors such as those used to power a RV's refrigerated air conditioning unit, for example, are particularly vulnerable to damage due to operation on low voltage alternating current. Furthermore, a low voltage condition sufficient to damage a piece of electrical equipment may not be noticeable from the outward appearance or operation of the device. Also, a device, such as a RV air conditioning unit, may be adapted to operate at times when the RV occupants are asleep and unable to detect any hint that might indicate a low voltage situation.
It is therefore a general object of the invention to provide a low voltage warning apparatus adapted to provide a suitable indication when a harmful low voltage condition exists. Another object of the invention is to provide a method for providing a low voltage indicating signal to alert a person to a low voltage condition.